summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
blob: cc96c27311345fdbd28220b2b89a4fccee575f00 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
/*******************************************************************************
 * IBM Virtual SCSI Target Driver
 * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
 *			   Santiago Leon (santil@us.ibm.com) IBM Corp.
 *			   Linda Xie (lxie@us.ibm.com) IBM Corp.
 *
 * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
 * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
 * Copyright (C) 2016 Bryant G. Ly <bryantly@linux.vnet.ibm.com> IBM Corp.
 *
 * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
 * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 ****************************************************************************/

#ifndef __H_IBMVSCSI_TGT
#define __H_IBMVSCSI_TGT

#include <linux/interrupt.h>
#include "libsrp.h"

#define SYS_ID_NAME_LEN		64
#define PARTITION_NAMELEN	96
#define IBMVSCSIS_NAMELEN       32

#define MSG_HI  0
#define MSG_LOW 1

#define MAX_CMD_Q_PAGES       4
#define CRQ_PER_PAGE          (PAGE_SIZE / sizeof(struct viosrp_crq))
/* in terms of number of elements */
#define DEFAULT_CMD_Q_SIZE    CRQ_PER_PAGE
#define MAX_CMD_Q_SIZE        (DEFAULT_CMD_Q_SIZE * MAX_CMD_Q_PAGES)

#define SRP_VIOLATION           0x102  /* general error code */

/*
 * SRP buffer formats defined as of 16.a supported by this driver.
 */
#define SUPPORTED_FORMATS  ((SRP_DATA_DESC_DIRECT << 1) | \
			    (SRP_DATA_DESC_INDIRECT << 1))

#define SCSI_LUN_ADDR_METHOD_FLAT	1

struct dma_window {
	u32 liobn;	/* Unique per vdevice */
	u64 tce_base;	/* Physical location of the TCE table */
	u64 tce_size;	/* Size of the TCE table in bytes */
};

struct target_dds {
	u64 unit_id;                /* 64 bit will force alignment */
#define NUM_DMA_WINDOWS 2
#define LOCAL  0
#define REMOTE 1
	struct dma_window  window[NUM_DMA_WINDOWS];

	/* root node property "ibm,partition-no" */
	uint partition_num;
	char partition_name[PARTITION_NAMELEN];
};

#define MAX_NUM_PORTS        1
#define MAX_H_COPY_RDMA      (128 * 1024)

#define MAX_EYE   64

/* Return codes */
#define ADAPT_SUCCESS            0L
/* choose error codes that do not conflict with PHYP */
#define ERROR                   -40L

struct format_code {
	u8 reserved;
	u8 buffers;
};

struct client_info {
#define SRP_VERSION "16.a"
	char srp_version[8];
	/* root node property ibm,partition-name */
	char partition_name[PARTITION_NAMELEN];
	/* root node property ibm,partition-no */
	u32 partition_number;
	/* initially 1 */
	u32 mad_version;
	u32 os_type;
};

/*
 * Changing this constant changes the number of seconds to wait before
 * considering the client will never service its queue again.
 */
#define SECONDS_TO_CONSIDER_FAILED 30
/*
 * These constants set the polling period used to determine if the client
 * has freed at least one element in the response queue.
 */
#define WAIT_SECONDS 1
#define WAIT_NANO_SECONDS 5000
#define MAX_TIMER_POPS ((1000000 / WAIT_NANO_SECONDS) * \
			SECONDS_TO_CONSIDER_FAILED)
/*
 * general purpose timer control block
 * which can be used for multiple functions
 */
struct timer_cb {
	struct hrtimer timer;
	/*
	 * how long has it been since the client
	 * serviced the queue. The variable is incrmented
	 * in the service_wait_q routine and cleared
	 * in send messages
	 */
	int timer_pops;
	/* the timer is started */
	bool started;
};

struct cmd_queue {
	/* kva */
	struct viosrp_crq *base_addr;
	dma_addr_t crq_token;
	/* used to maintain index */
	uint mask;
	/* current element */
	uint index;
	int size;
};

#define SCSOLNT_RESP_SHIFT	1
#define UCSOLNT_RESP_SHIFT	2

#define SCSOLNT         BIT(SCSOLNT_RESP_SHIFT)
#define UCSOLNT         BIT(UCSOLNT_RESP_SHIFT)

enum cmd_type {
	SCSI_CDB	= 0x01,
	TASK_MANAGEMENT	= 0x02,
	/* MAD or addressed to port 0 */
	ADAPTER_MAD	= 0x04,
	UNSET_TYPE	= 0x08,
};

struct iu_rsp {
	u8 format;
	u8 sol_not;
	u16 len;
	/* tag is just to help client identify cmd, so don't translate be/le */
	u64 tag;
};

struct ibmvscsis_cmd {
	struct list_head list;
	/* Used for TCM Core operations */
	struct se_cmd se_cmd;
	struct iu_entry *iue;
	struct iu_rsp rsp;
	struct work_struct work;
	struct scsi_info *adapter;
	struct ibmvscsis_cmd *abort_cmd;
	/* Sense buffer that will be mapped into outgoing status */
	unsigned char sense_buf[TRANSPORT_SENSE_BUFFER];
	u64 init_time;
#define CMD_FAST_FAIL	BIT(0)
#define DELAY_SEND	BIT(1)
	u32 flags;
	char type;
};

struct ibmvscsis_nexus {
	struct se_session *se_sess;
};

struct ibmvscsis_tport {
	/* SCSI protocol the tport is providing */
	u8 tport_proto_id;
	/* ASCII formatted WWPN for SRP Target port */
	char tport_name[IBMVSCSIS_NAMELEN];
	/* Returned by ibmvscsis_make_tport() */
	struct se_wwn tport_wwn;
	/* Returned by ibmvscsis_make_tpg() */
	struct se_portal_group se_tpg;
	/* ibmvscsis port target portal group tag for TCM */
	u16 tport_tpgt;
	/* Pointer to TCM session for I_T Nexus */
	struct ibmvscsis_nexus *ibmv_nexus;
	bool enabled;
	bool releasing;
};

struct scsi_info {
	struct list_head list;
	char eye[MAX_EYE];

	/* commands waiting for space on repsonse queue */
	struct list_head waiting_rsp;
#define NO_QUEUE                    0x00
#define WAIT_ENABLED                0X01
#define WAIT_CONNECTION             0x04
	/* have established a connection */
#define CONNECTED                   0x08
	/* at least one port is processing SRP IU */
#define SRP_PROCESSING              0x10
	/* remove request received */
#define UNCONFIGURING               0x20
	/* disconnect by letting adapter go idle, no error */
#define WAIT_IDLE                   0x40
	/* disconnecting to clear an error */
#define ERR_DISCONNECT              0x80
	/* disconnect to clear error state, then come back up */
#define ERR_DISCONNECT_RECONNECT    0x100
	/* disconnected after clearing an error */
#define ERR_DISCONNECTED            0x200
	/* A series of errors caused unexpected errors */
#define UNDEFINED                   0x400
	u16  state;
	int fast_fail;
	struct target_dds dds;
	char *cmd_pool;
	/* list of free commands */
	struct list_head free_cmd;
	/* command elements ready for scheduler */
	struct list_head schedule_q;
	/* commands sent to TCM */
	struct list_head active_q;
	caddr_t *map_buf;
	/* ioba of map buffer */
	dma_addr_t map_ioba;
	/* allowable number of outstanding SRP requests */
	int request_limit;
	/* extra credit */
	int credit;
	/* outstanding transactions against credit limit */
	int debit;

	/* allow only one outstanding mad request */
#define PROCESSING_MAD                0x00002
	/* Waiting to go idle */
#define WAIT_FOR_IDLE		      0x00004
	/* H_REG_CRQ called */
#define CRQ_CLOSED                    0x00010
	/* detected that client has failed */
#define CLIENT_FAILED                 0x00040
	/* detected that transport event occurred */
#define TRANS_EVENT                   0x00080
	/* don't attempt to send anything to the client */
#define RESPONSE_Q_DOWN               0x00100
	/* request made to schedule disconnect handler */
#define SCHEDULE_DISCONNECT           0x00400
	/* disconnect handler is scheduled */
#define DISCONNECT_SCHEDULED          0x00800
	/* remove function is sleeping */
#define CFG_SLEEPING                  0x01000
	/* Register for Prepare for Suspend Transport Events */
#define PREP_FOR_SUSPEND_ENABLED      0x02000
	/* Prepare for Suspend event sent */
#define PREP_FOR_SUSPEND_PENDING      0x04000
	/* Resume from Suspend event sent */
#define PREP_FOR_SUSPEND_ABORTED      0x08000
	/* Prepare for Suspend event overwrote another CRQ entry */
#define PREP_FOR_SUSPEND_OVERWRITE    0x10000
	u32 flags;
	/* adapter lock */
	spinlock_t intr_lock;
	/* information needed to manage command queue */
	struct cmd_queue cmd_q;
	/* used in hcall to copy response back into srp buffer */
	u64  empty_iu_id;
	/* used in crq, to tag what iu the response is for */
	u64  empty_iu_tag;
	uint new_state;
	uint resume_state;
	/* control block for the response queue timer */
	struct timer_cb rsp_q_timer;
	/* keep last client to enable proper accounting */
	struct client_info client_data;
	/* what can this client do */
	u32 client_cap;
	/*
	 * The following two fields capture state and flag changes that
	 * can occur when the lock is given up.  In the orginal design,
	 * the lock was held during calls into phyp;
	 * however, phyp did not meet PAPR architecture.  This is
	 * a work around.
	 */
	u16  phyp_acr_state;
	u32 phyp_acr_flags;

	struct workqueue_struct *work_q;
	struct completion wait_idle;
	struct completion unconfig;
	struct device dev;
	struct vio_dev *dma_dev;
	struct srp_target target;
	struct ibmvscsis_tport tport;
	struct tasklet_struct work_task;
	struct work_struct proc_work;
};

/*
 * Provide a constant that allows software to detect the adapter is
 * disconnecting from the client from one of several states.
 */
#define IS_DISCONNECTING (UNCONFIGURING | ERR_DISCONNECT_RECONNECT | \
			  ERR_DISCONNECT)

/*
 * Provide a constant that can be used with interrupt handling that
 * essentially lets the interrupt handler know that all requests should
 * be thrown out,
 */
#define DONT_PROCESS_STATE (IS_DISCONNECTING | UNDEFINED | \
			    ERR_DISCONNECTED  | WAIT_IDLE)

/*
 * If any of these flag bits are set then do not allow the interrupt
 * handler to schedule the off level handler.
 */
#define BLOCK (DISCONNECT_SCHEDULED)

/* State and transition events that stop the interrupt handler */
#define TARGET_STOP(VSCSI) (long)(((VSCSI)->state & DONT_PROCESS_STATE) | \
				  ((VSCSI)->flags & BLOCK))

#define PREP_FOR_SUSPEND_FLAGS  (PREP_FOR_SUSPEND_ENABLED | \
				 PREP_FOR_SUSPEND_PENDING | \
				 PREP_FOR_SUSPEND_ABORTED | \
				 PREP_FOR_SUSPEND_OVERWRITE)

/* flag bit that are not reset during disconnect */
#define PRESERVE_FLAG_FIELDS (PREP_FOR_SUSPEND_FLAGS)

#define vio_iu(IUE) ((union viosrp_iu *)((IUE)->sbuf->buf))

#define READ_CMD(cdb)	(((cdb)[0] & 0x1F) == 8)
#define WRITE_CMD(cdb)	(((cdb)[0] & 0x1F) == 0xA)

#ifndef H_GET_PARTNER_INFO
#define H_GET_PARTNER_INFO              0x0000000000000008LL
#endif
#ifndef H_ENABLE_PREPARE_FOR_SUSPEND
#define H_ENABLE_PREPARE_FOR_SUSPEND    0x000000000000001DLL
#endif
#ifndef H_READY_FOR_SUSPEND
#define H_READY_FOR_SUSPEND             0x000000000000001ELL
#endif


#define h_copy_rdma(l, sa, sb, da, db) \
		plpar_hcall_norets(H_COPY_RDMA, l, sa, sb, da, db)
#define h_vioctl(u, o, a, u1, u2, u3, u4) \
		plpar_hcall_norets(H_VIOCTL, u, o, a, u1, u2)
#define h_reg_crq(ua, tok, sz) \
		plpar_hcall_norets(H_REG_CRQ, ua, tok, sz)
#define h_free_crq(ua) \
		plpar_hcall_norets(H_FREE_CRQ, ua)
#define h_send_crq(ua, d1, d2) \
		plpar_hcall_norets(H_SEND_CRQ, ua, d1, d2)

#endif